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2.
Endocrinology ; 163(12)2022 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-36181426

RESUMO

Estrogen receptor alpha (ERα)-mediated estrogen signaling plays a pivotal role in both reproductive and nonreproductive functions. Transcriptional regulation of the ERα gene is highly complex, with multiple transcript variants being differentially produced across the tissues. However, tissue-specific variation and physiological specificity of the ERα variants are not yet fully understood. In an attempt to generate a Cre-dependently restorable ERα-null mouse for functional genetic studies, we unexpectedly produced ERα hypomorphic mice with biased downregulation of a previously unappreciated long ERα isoform that is enriched in the female reproductive organs (uterus and ovaries) and the pituitary but minimally expressed in the brain. Female homozygous mutant mice were capable of pregnancy but displayed irregular estrus cycle and rarely kept newborn pups alive. No significant morphological and pathological changes in reproductive system or disruption of body weight homeostasis were seen in female homozygous mutant mice. Collectively, our results define a tissue-specific enriched long ERα isoform and its preferential role in female reproductive function rather than body weight homeostasis.


Assuntos
Receptor alfa de Estrogênio , Estrogênios , Fenômenos Reprodutivos Fisiológicos , Animais , Feminino , Camundongos , Peso Corporal , Receptor alfa de Estrogênio/genética , Camundongos Knockout , Isoformas de Proteínas , Fenômenos Reprodutivos Fisiológicos/genética
4.
N Z Med J ; 132(1488): 11-20, 2019 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-31851657

RESUMO

AIM: Unnecessary treatment of asymptomatic bacteriuria is a concern. Hutt Valley District Health Board sought to reduce clinically inappropriate urine culture requests through removal of urine dipsticks from wards and education of staff using Choosing Wisely principles. The purpose of this research is to quantitatively evaluate the success of these initiatives. METHODS: The numbers and results of urine cultures performed for Hutt Valley DHB were analysed, for the period from January 2015 to October 2017. Urinalyses were compared between those designated as 'inpatient' and those as 'outpatient', with the latter being the control of this study. The numbers of primary and secondary coded discharge diagnoses of UTIs were used as a measure of the negative impact of the interventions. RESULTS: There was a 28% reduction in monthly urine culture requests for inpatients, after staff education and removal of urine dipsticks, with no change in those for outpatients (the negative control). After the intervention, a higher proportion of urine cultures were positive for urinary pathogens (25.2% compared to 23.0%) and the average number of diagnoses of UTI in hospital discharges decreased 17% (from 161 to 134). CONCLUSION: The removal of urine dipsticks from wards and the education of staff significantly reduced the number of urine culture requests and is a useful strategy to reduce the overuse of antibiotics for asymptomatic bacteriuria without an increase in the number of UTIs. These simple interventions could be used at other hospitals as part of measures to reduce unnecessary care and overdiagnosis.


Assuntos
Sobremedicalização/prevenção & controle , Procedimentos Desnecessários/estatística & dados numéricos , Urinálise/estatística & dados numéricos , Adulto , Educação em Saúde , Humanos , Sobremedicalização/economia , Sobremedicalização/estatística & dados numéricos , Nova Zelândia , Procedimentos Desnecessários/economia , Urinálise/economia , Urinálise/métodos , Infecções Urinárias/diagnóstico , Infecções Urinárias/microbiologia
5.
Int J Mol Sci ; 20(19)2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31546645

RESUMO

Abdominal aortic aneurysm (AAA) is among the top 20 causes of death in the United States. Surgical repair is the gold standard for AAA treatment, therefore, there is a need for non-invasive therapeutic interventions. Aneurysms are more closely associated with the osteoclast-like catabolic degradation of the artery, rather than the osteoblast-like anabolic processes of arterial calcification. We have reported the presence of osteoclast-like cells (OLCs) in human and mouse aneurysmal tissues. The aim of this study was to examine OLCs from aneurysmal tissues as a source of degenerative proteases. Aneurysmal and control tissues from humans, and from the mouse CaPO4 and angiotensin II (AngII) disease models, were analyzed via flow cytometry and immunofluorescence for the expression of osteoclast markers. We found higher expression of the osteoclast markers tartrate-resistant acid phosphatase (TRAP), matrix metalloproteinase-9 (MMP-9), and cathepsin K, and the signaling molecule, hypoxia-inducible factor-1α (HIF-1α), in aneurysmal tissue compared to controls. Aneurysmal tissues also contained more OLCs than controls. Additionally, more OLCs from aneurysms express HIF-1α, and produce more MMP-9 and cathepsin K, than myeloid cells from the same tissue. These data indicate that OLCs are a significant source of proteases known to be involved in aortic degradation, in which the HIF-1α signaling pathway may play an important role. Our findings suggest that OLCs may be an attractive target for non-surgical suppression of aneurysm formation due to their expression of degradative proteases.


Assuntos
Aneurisma da Aorta Abdominal/enzimologia , Osteoclastos/enzimologia , Animais , Aneurisma da Aorta Abdominal/metabolismo , Catepsina K/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Macrófagos/enzimologia , Macrófagos/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células Mieloides/metabolismo , Osteoclastos/metabolismo , Proteólise , Células RAW 264.7 , Fosfatase Ácida Resistente a Tartarato/metabolismo
6.
Infect Dis Poverty ; 8(1): 33, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31097018

RESUMO

In the original publication of this article [1], there is an error in the section of 'Ethics approval and consent to participate' at the end of the article, the correct Ethics reference number should be HE551404 rather than HE591067.

7.
J Vasc Res ; 56(2): 55-64, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31085912

RESUMO

BACKGROUND: Even though hypoxia-inducible factor-1α (HIF-1α) is among the transcriptional factors demonstrated to contribute to the formation of abdominal aortic aneurysms (AAAs), the precise mechanism has been unclear. Digoxin is known as an inhibitor of HIF-1α, and shows a protective effect against the progression of AAAs. OBJECTIVES: We tested the effect of digoxin on osteoclastogenesis (OCG) and examined the pathway through which digoxin exerts inhibition of HIF-1α. MATERIALS AND METHODS: RAW 264.7 macrophage cells were cultured and stimulated by soluble receptor activator of NF-κB ligand (sRANKL) with or without digoxin. First, we tested the effect of digoxin to attenuate macrophage activation, which led to OCG, characterized by tartrate-resistant acid phosphatase (TRAP)-positive macrophages (TPMs). RESULTS: The activation of TPMs stimulated by sRANKL was attenuated by digoxin treatment. Furthermore, the receptor activator of NF-κB (RANK)/receptor activator of NF-κB ligand (RANKL) complex signaling pathway, which is stimulated by HIF-1α, was downregulated by digoxin treatment. CONCLUSIONS: These results show that digoxin attenuates OCG. By inhibition of HIF-1α, digoxin decreases OCG through the downregulation of the RANK/RANKL signaling pathway. Therefore, digoxin is a potential candidate for medical treatment of AAAs.


Assuntos
Aneurisma da Aorta Abdominal/tratamento farmacológico , Digoxina/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Ligante RANK/farmacologia , Animais , Aneurisma da Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Macrófagos/metabolismo , Camundongos , Osteoclastos/metabolismo , Células RAW 264.7 , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Transdução de Sinais
8.
J Vasc Res ; 56(3): 139-151, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31064000

RESUMO

BACKGROUND: It has been reported that smoking is one of the strongest positive risk factors for abdominal aortic aneurysms (AAAs). Although many studies have been directed to decipher the effect of smoking on AAA, its effect on macrophage activation has not yet been explored. OBJECTIVES: We have reported the importance of osteoclastogenesis (OCG) in aneurysm formation. Therefore, we examined the effect of cigarette smoking on OCG and arterial aneurysmal formation by using cigarette smoke extract (CSE) in this study. METHODS: Macrophage cell lines were stimulated with CSE, and their activation and differentiation were examined in vitro. Since macrophages activated through the OCG pathway are identified by tartrate-resistant acid phosphatase (TRAP) expression, these cells are referred to as TRAP-positive macrophages (TPMs) in this study. We also applied CSE-contained PBS in the calcium chloride-induced mouse carotid aneurysm model in vivo. RESULTS: Macrophages stimulated with CSE expressed significantly higher levels of nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), TRAP, cathepsin K, matrix metalloproteinase-9 and membrane-type metalloproteinase (MT1-MMP). CSE-treated mouse aneurysms showed increased aneurysm size with increased TPM infiltration and protease expression compared to non-CSE-treated mouse aneurysms. CONCLUSIONS: These results suggest that CSE intensifies OCG in macrophages and promotes arterial aneurysmal progression.


Assuntos
Aneurisma/induzido quimicamente , Doenças das Artérias Carótidas/induzido quimicamente , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fumaça/efeitos adversos , Fosfatase Ácida Resistente a Tartarato/metabolismo , Produtos do Tabaco/efeitos adversos , Aneurisma/enzimologia , Aneurisma/patologia , Animais , Cloreto de Cálcio , Doenças das Artérias Carótidas/enzimologia , Doenças das Artérias Carótidas/patologia , Catepsina K/metabolismo , Modelos Animais de Doenças , Macrófagos/enzimologia , Macrófagos/patologia , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Osteoclastos/enzimologia , Osteoclastos/patologia , Células RAW 264.7 , Transdução de Sinais
9.
Infect Dis Poverty ; 8(1): 18, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30890188

RESUMO

BACKGROUND: Opisthorchis viverrini infection is highly prevalent in northeast Thailand. This liver fluke is classified as a carcinogen due to its causal links with cholangiocarcinoma (CCA) development. Although treatment with praziquantel (PZQ) effectively cures O. viverrini infection, the prevalence remains high due to the traditional consumption of raw fish. Therefore, re-infection is common in the endemic community, leading to severe hepato-biliary morbidities including the fatal CCA. In this study, we evaluate the association between the frequency of previous PZQ treatment and current O. viverrini infections among Thai adults living in the endemic area of northeast Thailand. METHODS: This study includes all participants who were screened for O. viverrini infection in the Cholangiocarcinoma Screening and Care Program (CASCAP), northeast Thailand. History of PZQ treatment was recorded using a health questionnaire. O. viverrini infections were diagnosed using urine antigen detection. Associations between PZQ and O. viverrini were determined by adjusted odds ratio (aOR) and 95% confidence interval (CI) using multiple logistic regression. RESULTS: Among participants, 27.7% had previously been treated once with PZQ, 8.2% twice, 2.8% three times, and 3.5% more than three times. Current O. viverrini prevalence was 17% (n = 524). Compared with participants who never used PZQ, the aOR for infection among those who used the drug once was 1.09 (95% CI: 0.88-1.37), twice was 1.19 (95% CI: 0.85-1.68), three times was 1.28 (95% CI: 0.74-2.21), and more than three times was 1.86 (95% CI: 1.18-2.93; P = 0.007). CONCLUSIONS: The population with a frequent history of PZQ use and still continued raw fish consumption showed high levels of repeated reinfection with O. viverrini. They were infected, treated and re-infected repeatedly. These findings suggest that certain participants continue raw fish consumption even after previous infection. This is a particular problem in highly endemic areas for O. viverrini and increases the risk of CCA.


Assuntos
Anti-Helmínticos/uso terapêutico , Opistorquíase/tratamento farmacológico , Opistorquíase/epidemiologia , Praziquantel/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Neoplasias dos Ductos Biliares/complicações , Neoplasias dos Ductos Biliares/diagnóstico , Colangiocarcinoma/complicações , Colangiocarcinoma/diagnóstico , Estudos Transversais , Fezes/parasitologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Opistorquíase/complicações , Opisthorchis , Alimentos Crus/parasitologia , Recidiva , Fatores de Risco , Vigilância de Evento Sentinela , Inquéritos e Questionários , Tailândia/epidemiologia , Adulto Jovem
10.
Vaccine ; 35(35 Pt B): 4578-4582, 2017 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-28720280

RESUMO

AIM: To assess the impact of the introduction of rotavirus vaccination in New Zealand at a regional and national level, underlining the utility of a passively collected laboratory dataset. METHOD: Retrospective laboratory data for rotavirus testing from Wellington and Hutt Hospitals from 1 January 2010 to 31 December 2016, matched with hospital admissions data of children under 5years of age with gastroenteritis primary and secondary coded admissions. The second part of the study examined the national dataset of primary coded hospital gastroenteritis admissions from the same period. RESULTS: Rotavirus testing was performed in 1054 (64.1%) of the 1645 gastroenteritis admissions to Wellington and Hutt Hospitals. Four hundred and nine of these tests (38.8%) were positive. Children who were not given a primary code of gastroenteritis accounted for 5.7% of rotavirus admissions. The estimated annual rotavirus hospitalisation rate in the Hutt and Wellington regions for children under 5years during the pre-vaccination period was 427.1 per 100,000. In the post-vaccination period (2015-2016), there was a 94.6% reduction in confirmed rotavirus gastroenteritis hospitalisations with only 8 confirmed cases. The total number of gastroenteritis admissions declined by 51.4%. On a national scale, there was a decline of 34.4% in the average annual number of gastroenteritis admissions and the number of coded rotavirus admissions was 87.1% lower than the pre-vaccination average. CONCLUSION: The non-restrictive continuous approach to rotavirus testing has provided a detailed description of the epidemiology of rotavirus gastroenteritis hospitalisations in the Wellington and Hutt regions. Rotavirus vaccination introduced on the crest of a peak in rotavirus cases has lead to a marked reduction in the number of admissions with gastroenteritis in New Zealand in the two years following vaccine introduction. The national figures likely underestimate the impact of the vaccine.


Assuntos
Gastroenterite/epidemiologia , Infecções por Rotavirus/epidemiologia , Vacinas contra Rotavirus , Vacinação/estatística & dados numéricos , Pré-Escolar , Infecção Hospitalar/epidemiologia , Bases de Dados Factuais , Feminino , Gastroenterite/virologia , Hospitalização , Humanos , Programas de Imunização , Lactente , Recém-Nascido , Laboratórios , Masculino , Nova Zelândia/epidemiologia , Estudos Retrospectivos , Infecções por Rotavirus/virologia , Vacinas contra Rotavirus/administração & dosagem , Software , Estatística como Assunto
11.
J Shoulder Elbow Surg ; 25(9): 1385-94, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27424254

RESUMO

BACKGROUND: Ultrasonography for the diagnosis of rotator cuff tears has been a topic of debate for years. The literature shows promising results for the diagnostic utility of ultrasonography for rotator cuff tears. This study assessed the effect of a surgeon-sonographer interaction on the ability of ultrasonography to predict the presence or absence of rotator cuff tears. METHODS: This study was a temporal cohort analysis of 775 patients to detect the diagnostic accuracy of ultrasonography at predicting a rotator cuff tear. The surgeon-sonographer interaction had three components: (1) presence of an ultrasound machine and ultrasonographer within a shoulder clinic, (2) the ultrasonographer attends shoulder operations, (3) and the ultrasonographer reviews patients preoperatively and postoperatively. Comparisons of 2 variables-presence and size of a tear-were made between the preoperative ultrasonographic findings with arthroscopic findings (gold standard). RESULTS: The diagnostic utility for the detection of rotator cuff tears by ultrasonography at the start of the study was 93% sensitive and 68% specific, and at the end of the study was 99% sensitive and 93% specific. There was an improvement in the correlation of the ability to estimate the size of rotator cuff tears from ultrasonography to surgery in both full- and partial-thickness tears. CONCLUSIONS: The surgeon-sonographer interaction improved the diagnostic utility of an office-based ultrasonographer over time, particularly with respect to the overall accuracy of ultrasonography for the detection of rotator cuff tears and for the ability to predict the size of full- and partial-thickness rotator cuff tears.


Assuntos
Relações Interprofissionais , Sistemas Automatizados de Assistência Junto ao Leito , Lesões do Manguito Rotador/diagnóstico por imagem , Cirurgiões , Ultrassonografia , Estudos de Coortes , Humanos , Funções Verossimilhança , Sensibilidade e Especificidade
12.
BMC Genomics ; 16: 384, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25975716

RESUMO

BACKGROUND: Previous genome-wide association analyses identified QTL regions in the X chromosome for percentage of normal sperm and scrotal circumference in Brahman and Tropical Composite cattle. These traits are important to be studied because they are indicators of male fertility and are correlated with female sexual precocity and reproductive longevity. The aim was to investigate candidate genes in these regions and to identify putative causative mutations that influence these traits. In addition, we tested the identified mutations for female fertility and growth traits. RESULTS: Using a combination of bioinformatics and molecular assay technology, twelve non-synonymous SNPs in eleven genes were genotyped in a cattle population. Three and nine SNPs explained more than 1% of the additive genetic variance for percentage of normal sperm and scrotal circumference, respectively. The SNPs that had a major influence in percentage of normal sperm were mapped to LOC100138021 and TAF7L genes; and in TEX11 and AR genes for scrotal circumference. One SNP in TEX11 was explained ~13% of the additive genetic variance for scrotal circumference at 12 months. The tested SNP were also associated with weight measurements, but not with female fertility traits. CONCLUSIONS: The strong association of SNPs located in X chromosome genes with male fertility traits validates the QTL. The implicated genes became good candidates to be used for genetic evaluation, without detrimentally influencing female fertility traits.


Assuntos
Bovinos/crescimento & desenvolvimento , Bovinos/genética , Mutação , Fenótipo , Carne Vermelha , Cromossomo X/genética , Andrologia , Animais , Bovinos/anatomia & histologia , Bovinos/fisiologia , Feminino , Fertilidade/genética , Técnicas de Genotipagem , Desequilíbrio de Ligação , Masculino , Polimorfismo de Nucleotídeo Único , Escroto/anatomia & histologia , Espermatozoides/citologia
13.
Antimicrob Agents Chemother ; 57(9): 4566-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23817378

RESUMO

New treatment strategies are urgently needed to overcome early mortality in acute bacterial infections. Previous studies have shown that administration of a novel immunoactivating peptide (P4) alongside passive immunotherapy prevents the onset of septicemia and rescues mice from lethal invasive disease models of pneumococcal pneumonia and sepsis. In this study, using two diverse populations of adult volunteers, we determined whether P4 treatment of human alveolar macrophages would upregulate phagocytic killing of Streptococcus pneumoniae ex vivo. We also measured macrophage intracellular oxidation, cytokine secretion, and surface marker expression following stimulation. Peptide treatment showed enhanced bacterial killing in the absence of nonspecific inflammation, consistent with therapeutic potential. This is the first demonstration of P4 efficacy on ex vivo-derived human lung cells.


Assuntos
Macrófagos Alveolares/efeitos dos fármacos , Oligopeptídeos/farmacologia , Fagocitose/efeitos dos fármacos , Adulto , Biomarcadores/metabolismo , Células Cultivadas , Citocinas/biossíntese , Feminino , Expressão Gênica , Voluntários Saudáveis , Humanos , Macrófagos Alveolares/citologia , Macrófagos Alveolares/imunologia , Malaui , Masculino , Oxirredução , Fagocitose/imunologia , Streptococcus pneumoniae/crescimento & desenvolvimento , Reino Unido
14.
J Infect Dis ; 205(1): 106-10, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22075766

RESUMO

Mortality from adult bacterial meningitis exceeds 50% in sub-Saharan Africa. We postulated that-particularly in individuals infected with human immunodeficiency virus (HIV)-herpes simplex virus, varicella zoster virus, Epstein-Barr virus (EBV), and cytomegalovirus (CMV) in the cerebrospinal fluid (CSF) contribute to poor outcome. CSF from 149 Malawian adults with bacterial meningitis and 39 controls were analyzed using polymerase chain reaction. EBV was detected in 79 of 149 bacterial meningitis patients. Mortality (54%) was associated with higher CSF EBV load when adjusted for HIV (P = .01). CMV was detected in 11 of 115 HIV-infected patients, 8 of whom died. The mechanisms by which EBV and CMV contribute to poor outcome require further investigation.


Assuntos
Coinfecção/mortalidade , Infecções por Citomegalovirus/complicações , Citomegalovirus/isolamento & purificação , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/isolamento & purificação , Meningites Bacterianas/mortalidade , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Coinfecção/líquido cefalorraquidiano , Coinfecção/complicações , Coinfecção/epidemiologia , Citomegalovirus/genética , Infecções por Citomegalovirus/líquido cefalorraquidiano , DNA Viral/líquido cefalorraquidiano , Infecções por Vírus Epstein-Barr/líquido cefalorraquidiano , Feminino , Infecções por HIV/líquido cefalorraquidiano , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/isolamento & purificação , Herpesvirus Humano 2/genética , Herpesvirus Humano 2/isolamento & purificação , Herpesvirus Humano 3/genética , Herpesvirus Humano 3/isolamento & purificação , Herpesvirus Humano 4/genética , Humanos , Modelos Logísticos , Malaui , Masculino , Meningites Bacterianas/líquido cefalorraquidiano , Meningites Bacterianas/complicações , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Estudos Prospectivos , Adulto Jovem
15.
J Bone Joint Surg Am ; 89 Suppl 2 Pt.1: 80-92, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17332127

RESUMO

BACKGROUND: A vastus-splitting approach for total knee arthroplasty has been advocated to preserve function of the extensor mechanism and to decrease the prevalence of lateral release. Critics have claimed that there is greater blood loss and compromised exposure in large patients who are managed with this approach. The purpose of the present study was to compare vastus-splitting and median parapatellar approaches for primary total knee arthroplasty. METHODS: Forty-two consecutive patients (fifty-one knees) undergoing primary total knee arthroplasty were randomized to treatment with a median parapatellar or vastus-splitting approach. The interval of the vastus muscle split was marked with radiopaque vascular clips. Surgical data, functional parameters, and preoperative and postoperative electromyograms were assessed. RESULTS: Early (six-month) and intermediateterm (five-year) follow-up showed no differences in functional parameters, tourniquet time, or the frequency of patellar resurfacing. Significantly more lateral releases (p < 0.01) and greater blood loss (p = 0.03) occurred in the median parapatellar group. Nine (43%) of twenty-one knees in the vastus-splitting group had abnormal electromyographic findings at six months postoperatively, whereas all patients in the median parapatellar group had normal findings. Seven knees with abnormal electromyographic findings at six months had normal findings when restudied at five years; in each of these knees, the vastus split had been developed bluntly. The other two knees with abnormal findings at six months had had sharp dissection for the muscle split. Both of these knees had chronic changes, one with changes indicative of reinnervation and the other with ongoing denervation, but neither demonstrated functional compromise. CONCLUSIONS: The vastus-splitting approach offers a viable alternative to the median parapatellar approach for primary total knee arthroplasty that reduces the need for lateral retinacular release without impairment of quadriceps function. Electromyographic abnormalities in the quadriceps muscle have no functional consequence and most likely represent reversible neurapraxic injury that may be avoided by blunt dissection in the vastus medialis muscle.


Assuntos
Artroplastia do Joelho/métodos , Perda Sanguínea Cirúrgica/prevenção & controle , Eletromiografia , Seguimentos , Humanos , Estudos Prospectivos
16.
J Bone Joint Surg Am ; 88(4): 715-20, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16595460

RESUMO

BACKGROUND: A vastus-splitting approach for total knee arthroplasty has been advocated to preserve function of the extensor mechanism and to decrease the prevalence of lateral release. Critics have claimed that there is greater blood loss and compromised exposure in large patients who are managed with this approach. The purpose of the present study was to compare vastus-splitting and median parapatellar approaches for primary total knee arthroplasty. METHODS: Forty-two consecutive patients (fifty-one knees) undergoing primary total knee arthroplasty were randomized to treatment with a median parapatellar or vastus-splitting approach. The interval of the vastus muscle split was marked with radiopaque vascular clips. Surgical data, functional parameters, and preoperative and postoperative electromyograms were assessed. RESULTS: Early (six-month) and intermediate-term (five-year) follow-up showed no differences in functional parameters, tourniquet time, or the frequency of patellar resurfacing. Significantly more lateral releases (p < 0.01) and greater blood loss (p = 0.03) occurred in the median parapatellar group. Nine (43%) of twenty-one knees in the vastus-splitting group had abnormal electromyographic findings at six months postoperatively, whereas all patients in the median parapatellar group had normal findings. Seven knees with abnormal electromyographic findings at six months had normal findings when restudied at five years; in each of these knees, the vastus split had been developed bluntly. The other two knees with abnormal findings at six months had had sharp dissection for the muscle split. Both of these knees had chronic changes, one with changes indicative of reinnervation and the other with ongoing denervation, but neither demonstrated functional compromise. CONCLUSIONS: The vastus-splitting approach offers a viable alternative to the median parapatellar approach for primary total knee arthroplasty that reduces the need for lateral retinacular release without impairment of quadriceps function. Electromyographic abnormalities in the quadriceps muscle have no functional consequence and most likely represent reversible neurapraxic injury that may be avoided by blunt dissection in the vastus medialis muscle.


Assuntos
Artroplastia do Joelho/métodos , Idoso , Eletromiografia , Humanos , Articulação do Joelho/fisiologia , Estudos Prospectivos , Fatores de Tempo
17.
Dialogue Can Philos Assoc ; 17(1): 122-4, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-11664128
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